Floating roof



Oct. 24, 1933. D. E, LARSON 1,931,551

FLOATING ROOF Filed June 15, 1952 4 Sheets-Sheet 1 06L 1933- D. E. LARSON 1,931,551

FLOATING ROOF Filed June 15, 1 952 I 4 Sheets-Shet 2 o zczZd if 627 1 07;

ff veflzor I Oct. 24, 1933. E, LARSON 1,931,551

FLOATING ROOF Filed June 15', 1952 4 SheetsSheet 4 Patented Oct. 24, 1933 UNITED STATES FLOATING ROOF Donald E. Larson, Chicago, 111.,

cago Bridge & Iron Company,

corporation of Illinois assignor to Chi- Chicago, m, a

Application June 13, 1932. Serial No. 616,987 9 Claims. (01. 220 -26) This invention relates'to improvements in floating roofs and, more especially, to such a floating roofas commonly employed in connection with oil tanks to lessen losses by evaporation.

Among the features of my invention is the provision of improved sealing means for such a floating roof and improved means for afiording fire protection.

My improved. sealing means is especially adapted for use in connection with a seal formed of shoes or segments of the type frequently em ployed in apparatus of the character referred to. My improvement in connection with the seal comprises primarily means for supporting said shoes; and means for urging the shoes into contact with the wall of the tank. 7

Other features and advantages of my invention will appear more fully as I proceed with my specification. v 29 In those forms of devices embodying the features of my invention shown in the accompanying drawings Figure 1 is a top plan view; Fig. 2 is a view taken as indicated by the line 2 of Fig. 1; Fig. 3 is a fragmentary view similar to Fig. 2 on an enlarged scale taken as indicated by the line 3 of Fig. 4; Fig. 4 is a plan view of the part shown in Fig. 3; Fig. 5 is a view taken as indicated by the line 5 of Fig. 3; Fig. 6 is a fragmentary view similar to Fig. 3 showing a modification; and similar to Fig. '3 showing the Fig. 7 is a view use of fire resisting foam. v

As shown in the drawings, 10 indicates the usual cylindrical tank with oil or other liquid 11 therein. Resting on the surface of the liquid is a floating roof including a central crown or sheet metal portion 12, here shown as supported by the annular pontoon 13. In order to seal the space between the edge of the roof and the wall of the tank 10', there are provided a plurality of segmental seal sections, hereinafter referred to as shoes and indicated by 14, 14. The shoes 14 are substantially vertically arranged and have their upper and lower edges 14 and 14 curved inwardly somewhat to assist the shoes in riding over bolt heads, overlapping edges of plates and other unevenesses that there may be on the inner wall surface of the tank. The adjacent vertical edges of the shoes 14 are preferably joined by flexible sealing material 17 suitably attached to the edges of the shoes in any well-known manner. In the form of device shown in all of the figures, except Fig. 6, each shoe is provided near .its upper edge with an inwardly extending pro- 55 jection or shield 14. The inner edge of this shield is joined to the periphery of the roof by a flexible seal 16 in any manner well known to the art. Adjacent edges of the extensions 14. are also preferably joined by flexible sealing material 17.

I shall now describe in detail my improved means for supporting the shoes 14 to permit radial movement thereof, with means for urging the same against the tank wall. Such means includes a substantially vertically arranged sup porting lever 18 pivotally attached to the roof at 19 near the periphery of the latter. As here shown, the lever 18 is made double, as shown in Fig. 4, so that its feet may be somewhat spread apart circumferentially, as indicated bythe two pivot points 19, 19 in Fig. 4. 20 indicates an angular radially arranged shoe supporting arm pivotally carried by the lever 18. This arm is bent at 20, as shown in Fig. 3, said band being located just'outside of and adjacent the pivotal support 21 of the arm 20 onthelever 18. The bend 20s divides the lever 20 into the outer portion 20 and the inner portion 20, the former being bent downwardly somewhat more sharply than the latter.

The shoe 14 is pivotally supported from the outer end of the arm 20 at 22. 23 indicates a connecting bar pivotally connecting the inner end of the shoe supporting arm 20 to the roof. The pivotal attachment of the arm 23 to the arm 20 is indicated by 24 and the pivotal attachment to the roof is indicated by 25, said attachment here being located on top of the axmular pontoon 13.

With the shoe support as shown, it will be seen that each shoe is free to move radially so that the shoes which form the segments of the seal may adjust themselves to variations in the space between the periphery of the roof and the wall of the tank in the manner common to seals for iloating roofs of the character referred to. In Fig.

3, the shoe is shown in solid lines in its innermost position and in broken lines in its outermost position. In the radial movements of the shoe, the lever 18 swings on the pivot 19. Consequently, the pivot point 21 moves in an arc and is at the highest point when the shoe is in substantially mid-position. -The swinging of the lever 20 with its inner end attached to the roof by the connecting bar 23 compensates somewhat for the arc-shaped path of the pivot point 21 so that the shoe 14 moves in substantially a straight path, as indicated by the direction line 26.

I also provide means for urging the shoe 14 into nosnosi contact with the inner wall surface oi the tank to. For tm purpose, I provide the lever 18 on upwardly arranged extension 18 to the end of which is attached the spring 27 with its lower end attached to the shoe 1% at 28. Tension oi the spring 37 tends to rock the lever 18 outwardly so that the shoe 14 is presed against the tank wall. Such pressure may be sufiicient to hold the shoe in parallel relation to and in con-= toot with the wall. This perellel relationship may also be aided by suitably balancing or weighting the shoe and arranging the pivot point 22 with respect thereto. It will be seen that by att the spring 27 to the shoe at a pops; in somewt shove the pivotal supporting point 22, the s ring pressure may also be utilized to tend to s 7 111:. the lower edge of the shoe outwardly or counteract any tendency for the same to swing inwwdly.

Theconnecting bar 23 is also here shown on double so that each her is provided with two separate pivotal supporting points 25 (see Fig. 4i). As here shown, the bar 23 is formed oi one piece bent in the middle, the bent portion forming a U-shaped extension 23 projecting shove the pivot point 2% and acting as a stop to limit the outward movement of the shoe when said portion 23 engages the arm 20 es shown by the broken lines in Fig. 3.

, in the modification shown in Fig. 6, the eirten= sion 1d of the shoe is omitted and the fabric seal lid correspondingto the seal 16 extends irom the periphery of the pontoon 113 entirely to the shoe lid. in other respects the construction is the some;

inside of the seai on top of the pontoon 13 is arranged a vertical dam 29 with its lower edge supported some distance above the roof in order to provide a crack-or space 30 under the dam. For fire protection it is contemplated that the space between the dam 29 and the shoes 1% oi the seal may be filled with lire resisting foam 31, for example, Foamite. The space 30 is e enough to permit water to drain thereunder but small enough to prevent the escape of the fire resisting ioaxnBl.

While I have shown and described certain embodiments of my invention, it is to be understood that it is capable of many modifications. Changes, therefore, in the construction and arrangement may be made without departing from the spirit and scope of the invention as disclosed in the appended claims, in which it is my intention. to claim all novelty inherent in my invention as broadly as permissible, in view of the prior sort.

What I regard as new, and desire to secure by Letters Patent, is:

1. A seal for a floating roof, including; a sub stentially vertically arranged lever pivotally attached to the roof near its periphery; a radial shoe supporting arm pivotally carried by said lever; a shoe pivotally supported from the outer end of said arm; and a connecting bar pivotally connecting the inner end of the shoe supporting arm to the roof.

2. Apparatus as claimed in claim 1, in which the radial shoe supporting arm has its outer portion bent downwardly.

3. Apparatus as claimed in claim 1, in which the shoe supporting arm has its outer and inner portions bent downwardly.

Apparatus as claimed in claim 1, in which the shoe supporting arm has its outer and inner portions bent downwardly, the outer portion being bent downwardly more than the inner portion.

5. Apparatus as claimed in claim 1, with spring means tending to rock the vertical lever outwerdly.

ii. Apperetus as claimed in claim 1, in which the vertical lever is provided with an upward extension, and a spring having one end connected to said extension and the other end connected to a part whereby the tension of said spring tends to rock the vertical lever outwardly.

'7. Apparatus as claimed in claim 1,.in which theconnecting bar is provided with an upward extension adapted to engage the shoe supporting arm to act as a. stop to limit the upward movement of the shoe.

8. A seal for, a floating roof, including; a substantially vertically arranged lever pivotaily at tached to the roof near its periphery; an angular radio-l shoe supporting arm pivotally carried by said lever; a shoe pivotally supported from the outer end of said arm and having a portion extending above said pivotal support; a connecting bar pivotally connecting the inner end of the shoe supporting arm to the roof; an extension on the vertical'lever projecting above the pivotal attachment of the radial shoe supporting arm thereto; and a spring connecting the upper end of said extension to the shoe above the point where the shoe is pivotally supported from the outer end of the shoe supporting arm.

9. A floating roof comprising; a flat central portion of substantial dimensions; and a surrounding exterior trough-like means for holding fire-resisting foam, the inner portion of said holding means constituting a dam between the trough and the flat central portion, the bottom of the dam being provided with leakage means for water.

DON E. LARSON.

Kidd 

